29 



arrived at tho interesting result, that beginning with air at 60' 

 Fahr., unlimited expansion would only lower it 550' ; while by 

 sufficiently increasing the compression, an infinite degree of heat 

 could be produced. 



The pi-actical result of the experiments and conclusions from 

 theory was to make the proposed method of cooling the air of 

 rooms (viz., by compressing the air, depriving it when compressed 

 of its extra heat, and then allowing it to escape into the room to be 

 cooled), — very possible indeed. 



While, to get over the difficulty that might be experienced in the 

 colonies of managing tho air pumps and coolers which would be re- 

 quired according to Professor P. S.'s plan, Mr Petrie proposed some 

 simple forms of water-pressure machines, and air-compressing 

 wheels. 



The following Gentleman was duly elected an Ordinary 

 Fellow : — 



Sir David Dundas, Bart., of Duneira. 



The following Donations to the Library were announced : — 



Proceedingsof the Royal Astronomical Society of London. Vol. II., 



No. 1. 8vo. — By the Society. 

 On the Cyclone of November 19 (1850). By the Rev. Humphrey 



Lloyd, D.D. 8vo. 

 On the Induction of Soft Iron, as applied to the determination of 



the changes of the Earth's Magnetic force. By the Rev. 



Humphrey Lloyd, D.D. 8vo. — By the Author. 

 Instructions for Making Meteorological and Tidal Observations. 



Prepared by the Council of the Royal Irish Academy. 8vo. 

 Second Report of the Council of the Royal Irish Academy, relative 



to tho establishment of a System of Meteorological and Tidal 



Observations in Ireland. 8vo. — By the Academy. 

 The London University Calendar. 1851. 12mo. — By the 



Publishers, 



